A car wash worker was seriously injured when he accidentally drove a customer's car off the third floor of an apartment in Malaysia.

The Afghan employee, 23, who was not named by authorities, mistakenly stepped on the accelerator while moving the newly cleaned Toyota Camry on June 15.

Dramatic dashcam CCTV footage shows the vehicle roaring across the carpark and slamming into a concrete wall. A loud crash was heard seconds later as it landed on its roof next to the service apartment in Kuala Lumpur.

The emergency services arrived and found the sedan lying upside-down on the street strewn with debris. An unoccupied orange car nearby sustained a large dent on its roof.

Rescuers extracted the severely injured worker from the carnage. He was rushed to the Universiti Malaya Medical Centre in critical condition.

Assistant Commissioner Mohd Zamzuri Mohd Isa, head of the Kuala Lumpur traffic investigation department, said: 'Initial investigations found that the man who worked as a car washer was believed to have lost control when he wanted to put away a customer's vehicle after washing it.

'It is believed that he mistakenly pressed the gas pedal, causing the vehicle to hit a wall and fall from the third floor before hitting two empty vehicles, namely the Proton Iriz and Perodua Myvi, which were parked under the adjacent building.'

He added that the case was being investigated under Section 43(1) of the Road Transport Act 1987.